Vitamin D: A Dermatologist’s Perspective

Vitamin D, which acts a both a vitamin and a hormone, is essential for good health. We have known for many years that vitamin deficiency can lead to rickets in children, softening of the bones in adults, called osteomalacia, and decreased bone mineral density leading to fragile bones, called osteoporosis. More recently vitamin D deficiency has been linked to other health problems including autoimmune diseases, such as psoriasis and lupus, frequent colds, depression, and muscle and joint pain. Deficiency may even be associated with an increased risk for some internal cancers. Natural sources of Vitamin D include foods (fish, fortified dairy products, fortified cereal, eggs, mushrooms) as well as sunlight, especially Ultraviolet B. This has led some health consultants to recommend 15 minutes of sun exposure daily. Many patients have asked me if they should abide by this recommendation and whether this is an argument against regular usage of sunscreen.

A study reported in the British Journal of Dermatology showed that regular sunscreen application failed to have an effect on Vitamin D status. The authors felt like this was largely related to the fact that very few patients adequately apply sunscreen to all sun-exposed skin daily. If a patient has had skin cancer or is at risk for other skin cancers, the risk of going without sunscreen, especially on areas with prior skin cancers, is significant. In choosing the best treatment for a condition or disease, physicians and patients as a rule, choose the treatment with the least risk or side effects. So it stands to reason that for the condition of vitamin D deficiency, treatment with UV radiation from the sun may be the more risky choice for treatment of the condition in patients who have had skin cancer, a family history of skin cancer or significant photo-aging.

Bottom line: Consider Vitamin D testing if you have not already had it. If you are deficient, the safest treatment is likely from daily dietary supplementation.